Water quality estimation by optical remote sensing in boreal lakes

Monitoring of lakes is mainly based on collection of water samples, which are transported to a laboratory for analyses. In lake-rich regions gathering of water quality information is challenging, because only a small proportion of the lakes can be assessed each year, often only a few times a year. One of the techniques for improving the temporal and spatial representativeness of lake monitoring is remote sensing.The main objectives of this study were to investigate and test remote sensing interpretation algorithms for water quality estimation in Finnish lakes, to develop optical models for the needs of interpretation and for the estimation of light attenuation, and to study the advantages of the use of remote sensing data as compared to the conventional monitoring methods. The experimental material included detailed optical measurements in 11 lakes, remote sensing measurements with concurrent in situ sampling, automatic raft measurements and a national dataset of routine water quality measurements. Remote sensing data consisted of airborne and satellite measurements (ETM+, ALI and MERIS).The analyses of the spatially high-resolution airborne remote sensing data of eutrophic and mesotrophic lakes showed that one or a few discrete water quality observations of conventional monitoring can yield a clear over- or underestimation of the overall water quality. The use of TM-type satellite instruments in addition to routine monitoring results substantially increases the number of lakes for which water quality information is obtained. The results indicated preliminarily that coloured dissolved organic matter (CDOM) can be estimated with TM-type satellite instruments, which could be possible  utilised as an aid in the estimation of the role of lakes in global carbon budgets. Based on the results of reflectance modelling and experimental data, MERIS satellite instrument has optimal or near-optimal channels for the estimation of turbidity, chlorophyll a and CDOM in Finnish lakes. MERIS images with 300 m spatial resolution can be utilised in production of water quality information in different parts of large and medium-size lakes, and in filling the gaps of conventional monitoring. Regional algorithms that would not require simultaneous in situ data for algorithm training would increase the amount of remote‑sensing-based information available for lake monitoring.  The MERIS Boreal Lakes processor, trained with the optical data and concentration ranges provided by this study, enabled turbidity estimation with good accuracy without need for algorithm correction with in situ measurements, while chlorophyll a and CDOM estimation requires further development of the processor. The accuracy of interpretation of chlorophyll a via semi‑empirical algorithms can be improved by classifying lakes prior to interpretation by CDOM level and trophic status, and by creating lake-type-specific algorithms. The results of optical modelling showed that spectral diffuse attenuation coefficient can be estimated with reasonable accuracy from the measured water quality concentrations. This provides more detailed information on light attenuation from routine monitoring measurements than is available through the Secchi disk transparency.This study improves the interpretation of water quality by remote sensing and encourages the use of remote sensing in lake monitoring.

Reduced tillage: Influence on erosion and nutrient losses in a clayey field in southern Finland

Reduced tillage was compared with traditional ploughing in terms of erosion and phosphorus (P) and nitrogen (N) losses in an experimental field in southern Finland. One part of the field has been ploughed (treatment PF) and the other part harrowed (treatment NPF) every autumn since 1986. Flow volume and water quality data was collected separately from surface runoff and subsurface drainage waters during 1991-1995 (surface runoff volume since 1993). Erosion was higher in PF (on average 234 kg ha-1yr-1 in drainage flow and 479 kg ha-1 yr-1 in surface runoff) than in NPF (158 kg ha-1yr-1 in drainage flow and 160 kg ha-1yr-1 in surface runoff). Total N loss in drainage flow was also higher in PF (7.2 kg ha-1yr-1) than in NPF (4.6 kg ha-1yr-1). Total P losses did not differ much; approximately 0.7 kg ha-1yr-1 was transported from both fields. Dissolved reactive P loss in surface runoff was higher in NPF (0.21 kg ha-1yr-1) than in PF (0.05 kg ha-1yr-1). This was probably attributable to the higher accumulation of P in the surface soil in NPF. The differences between the treatments were largely similar to those found in previous studies

Movesole älypohjallisilla mittaaminen

Jalkapohjaan kohdistuvien voimien arviointi on todettu yhdeksi tärkeäksi menetelmäksi arvioitaessa jalkaterän toimintoja. Erilaisia mittausmenetelmiä on kehitetty ammattilaisten käytettäväksi asiakasvastaanottotilanteissa. Voimien mittaaminen olisi kuitenkin hyödyllistä myös arkirutiineissa. Opinnäytetyö tehtiin yhteistyössä Movesole- yrityksen kanssa, joka on kehittänyt uudenlaisen älypohjallisjärjestelmän. Opinnäytetyön tarkoituksena oli arvioida Movesolen kehittämän älypohjallisjärjestelmän käyttökokemuksia. Opinnäytetyö käsittelee reaktiovoimia, plantaarista painetta ja voiman mittaamista. Tarkoituksena oli arvioida Movesolen kehittämän älypohjallisjärjestelmän käyttökokemuksia käyttäjien ja ammattilaisen näkökulmasta. Käyttäjien käyttökokemuksia kerättiin kyselylomakkeen avulla sekä mittaamalla aikaa, kuinka kauan laitteen käyttöönotto vei. Ammattilaisen käyttökokemuksia kerättiin kyselylomakkeen avulla ja tarkasteltiin mittaustuloksia kliinisessä mittaustilanteessa sekä kotikäytössä. Opinnäytetyön tutkimuksellinen lähestymistapa oli laadullinen ja määrällinen. Aineisto kerättiin tutkittaville sekä ammattilaiselle jaetuilla kyselylomakkeilla, tutkittavien päiväkirjoilla sekä käyttökokemuslomakkeilla. Tutkimusjoukko koostui neljästä 21-27- vuotiaasta perusterveestä henkilöistä. Käyttökokemuksien ja pohdinnan kannalta ammattilaisella ja käyttäjillä oli paljon yhteneviä kokemuksia pohjallisista. Tulokset olivat yksimielisiä siitä, että tuote voisi olla kaikista hyödyllisin diabeetikoilla, joilla on neuropatiasta johtuvia tuntopuutoksia ja suuri riski jalkahaavoille. Laite koettiin helppokäyttöiseksi, mielekkääksi ja sillä on matala kokeilukynnys. Pohjallisiin voitaisiin myös asentaa useampia sensoreita, jotta voiman jakautumisen mittaustulokset olisivat tarkempia. Jatkokehitys ehdotukseksi pohdittiin äänen yhdistämistä pohjallisiin, ohjeiden selkeyttämistä sekä sovelluksen kehittämistä soveltuvaksi muihinkin älypuhelimiin. Tällä hetkellä älypohjalliset soveltuvat ainoastaan Android laitteisiin. Pohjallisia itsessään suositeltiin kehitettävän huomaamattomammiksi ja niiden ulkoasun värit sellaisiksi, että käyttäjä osaa pukea ne oikein päin kenkiinsä. Kehitysehdotuksena olisi isommalla tutkimusryhmällä tutkiminen, jotta tuloksia saataisiin lisää.An assessment of the forces on the foot base has been identified as one of the important methods for assessing feet biomecanic. Various measurement methods have been developed for use by professionals in customer reception situations. Measuring force and plantar pressure would also be useful in daytime routines. The thesis work was done in cooperation with Movesole, which has developed a new kind of intelligent system. The purpose of this thesis was to evaluate the Movesole’s developed systems user experiences. The thesis deals with reaction forces, plantar pressure and force measurement. The purpose was to assess the Movesole’s developed system’s experience from the perspective of users and professional. Users' experience was collected by a questionnaire and measuring how long the device was started up. User’s experiences were collected using a questionnaire and examined the measurement results in clinical measurement and home use. The research approach of the thesis was qualitative and quantitative. The material was collected using questionnaires and diary. The research group consisted of four people aged 21-27 years. The professional and the users had a lot of similar experiences. The results were unanimous that the product could be the most useful in diabetics with neuropathic sensations and high risk of foot injuries. The device was thought to be easy to use, meaningful and has a low trial threshold. Multiple sensors could also be installed on the bottom so that the results of the distribution of power distribution would be more accurate. A further development of the proposal was to combine sound with the basics, clarify the instructions, and develop the application to suit other smartphones. System are only suitable for Android devices. Insoles themselves were recommended to become more discreet and their appearance colors so that the user can fit them properly in their shoes. The development plan would be to make a research to bigger group to get more results

Concurrent changes in dental anxiety and smoking in parents of the FinnBrain Birth Cohort Study

We evaluated associations between changes in dental anxiety and tobacco use, adjusted for general anxiety and depressive symptoms. The FinnBrain Birth Cohort Study data, collected at gestational weeks 14 and 34 and at 3 months postpartum, were used. Questionnaires included the Modified Dental Anxiety Scale (MDAS), the Edinburgh Postnatal Depression Scale (EPDS), and the anxiety subscale of the Symptom Checklist-90 (SCL). Smoking was categorized as "stable non-smoking", "started smoking", "quit smoking", and "stable smoking". Changes in smoking and dental anxiety were evaluated "during pregnancy" (i.e., from gestational week 14 to gestational week 34) in 2442 women and 1346 men and "after pregnancy" (i.e., from gestational week 34 to 3 months postpartum) in 2008 women and 1095 men. Changes were evaluated in three smoking categories (stable non-smoking, fluctuating, and stable smoking), using data from all three time-points (1979 women and 1049 men). Modeling used repeated measures analysis of covariance. Stable smoking mothers had statistically significantly higher levels of dental anxiety (mean MDAS 12.3-12.6) than non-smoking mothers (mean MDAS 10.1-10.7) or mothers who smoked at some point during pregnancy (mean MDAS 10.8-11.5). A similar tendency was observed in fathers. However, no systematic change in dental anxiety by changes in smoking habits was observed. Those smoking during pregnancy and with high dental anxiety may need special support for smoking cessation.Peer reviewe

Temporal patterns of phytoplankton phenology across high latitude lakes unveiled by long-term time series of satellite data

Monitoring temporal changes in phytoplankton dynamics in high latitude lakes is particularly timely for understanding the impacts of warming on aquatic ecosystems. In this study, we analyzed 33-years of high resolution (30 m) Landsat (LT) data for reconstructing seasonal patterns of chlorophyll a (chl a) concentration in four lakes across Finland, between 60°N and 64°N. Chl a models based on LT spectral bands were calibrated using 17-years (2000–2016) of field measurements collected across the four lakes. These models were then applied for estimating chl a using the entire LT-5 and 7 archives. Approximately 630 images, from 1984 to 2017, were analyzed for each lake. The chl a seasonal patterns were characterized using phenology metrics, and the time-series of LT-based chl a estimates were used for identifying temporal shifts in the seasonal patterns of chl a concentration. Our results showed an increase in the length of phytoplankton growth season in three of the lakes. The highest increase was observed in Lake Köyliönjärvi, where the length of growth season has increased by 28 days from the baseline period of 1984–1994 to 2007–2017. The increase in the length of season was mainly attributed to an earlier start of phytoplankton blooms. We further analyzed surface temperature (Ts) and precipitation data to verify if climatic factors could explain the shifts in the seasonal patterns of chl a. We found no direct relationship between Ts and chl a seasonal patterns. Similarly, the phenological metrics of Ts, in particular length of season, did not show significant temporal trends. On the other hand, we identify potential links between changes in precipitation patterns and the increase in the phytoplankton season length. We verified a significant increase in the rainfall contribution to the total precipitation during the autumn and winter, accompanied by a decline in snowfall volumes. This could indicate an increasing runoff volume during the beginning of spring, contributing to an earlier onset of the phytoplankton blooms, although further assessments are needed to analyze historical streamflow values and nearby land cover data. Likewise, additional studies are needed to better understand why chl a patterns in some lakes seem to be more resilient than in others.peerReviewe

Participatory operations model for cost-efficient monitoring and modeling of river basins — A systematic approach

AbstractThe worldwide economic downturn and the climate change in the beginning of 21st century have stressed the need for cost efficient and systematic operations model for the monitoring and management of surface waters. However, these processes are still all too fragmented and incapable to respond these challenges. For example in Finland, the estimation of the costs and benefits of planned management measures is insufficient. On this account, we present a new operations model to streamline these processes and to ensure the lucid decision making and the coherent implementation which facilitate the participation of public and all the involved stakeholders. The model was demonstrated in the real world management of a lake. The benefits, pitfalls and development needs were identified. After the demonstration, the operations model was put into operation and has been actively used in several other management projects throughout Finland

Substrate limitation of a habitat-forming genus Fucus under different water clarity scenarios in the northern Baltic Sea

Canopy-forming macroalgae living on rocky bottoms provide valuable ecosystem services but long-term eutrophication has narrowed their distribution and depth zonation in the Baltic Sea. The spatial distribution of macroalgae is shaped by many factors, such as light, salinity, nutrients and wave exposure. In addition, the lack of suitable hard substrates limits the distribution of algae in many areas. Analysing how the spatial distribution of macroalgae is modified by changes in environmental conditions is relevant for focusing management actions. To quantify the resultant distribution under various environmental and management scenarios, both current environmental conditions and substrate limitation need to be considered. We estimated the potential distribution area of bladderwrack Fucus spp. under 11 water transparency scenarios in 9 Finnish sea areas differing in morphology and eutrophication status. The prevailing averaged long-term water transparency conditions were interpreted from satellite images. Ten scenarios were calculated based on hypothetical changes in euphotic depth from −50% to +50% of the present. Species distribution modelling was used to assess the potential distribution areas of Fucus. In addition, to quantify the influence of substrate limitation, we estimated the average substrate limitation with two correction methods: (i) by using field data from underwater videos within the predicted distribution areas and (ii) by using a habitat model representing the distribution of reefs (i.e. rocky bottoms) in the study area. The decrease of euphotic depth by 50% from the present level narrowed the distribution area of Fucus by 24–53% in the Southwestern archipelago, 55–70% in the Gulf of Finland, 37–66% in the Bothnian Sea and 59–100% in Kvarken. An increase in euphotic depth significantly broadened the spatial distribution of Fucus. Decreasing share of suitable hard substrate along depth gradient however hinders broadening of the distribution area. If all areas were suitable for growth, a 50% increase in euphotic depth would expand the distribution area by 124–803%, depending on area. When only suitable substrates were taken into account, this percentage remained at 9–270%. We conclude that substrate limitation needs to be taken into account when estimating macroalgal species distribution in the marine environment. We show how this can be done also when comprehensive bottom substrate maps are not available. Our results are valuable when setting the targets for environmental management plans, and for balancing the local management measures in a cost effective manner. Highlights • Benthic light conditions affect the distribution of canopy-forming macroalgae Fucus. • Also substrate limits the distribution and zonation of Fucus. • Scenario modelling and substrate correction methods were utilised. • Sea areas differ in substrate composition which affects potential distribution area. • Substrate limitation is more pronounced in inner than in outer archipelago